Produced-water treatment: Application and research of combined fiber coalescence technique in offshore oilfield

When the process of extraction of oil from an offshore oilfield enters the advanced stages,the water content in the extracted fluid can be above 90%.The water quality is complex with many types of pollutants and highly emulsified water.Therefore,a key consideration in the production process of offshore oilfields is the efficient and economical treatment of the oil-containing produced water to make it suitable for discharge and recover oil pollutants.In this study,we developed a hydrophilic and hydrophobic combined fiber coalescence separator with composite fiber shapes using fiber induction and X/Uweaving.The separator is designed based on experimental observations of the mechanism of structure coalescence in the physical oil removal method.A pilot test was performed on an oil exploration platform in the Bohai Sea.At the designed flow rate,the separator reduced the total concentration of petroleum in the produced water from 2000 to 3000 mg/L to below 60 mg/L,with an average oil removal efficiency of 98.24%.Furthermore,it effectively reduced the number of organic compounds present in the water from 120 to 17 and removed 70% of the SS.The test results show that the proposed device can be used fr produced-water treatment on offshore platforms.

Compact generation scheme of path–frequency hyperentangled photons using 2D periodical nonlinear photonic crystal

Hyperentanglement is a promising resource for achieving high capacity quantum communication.Here,we propose a compact scheme for the generation of path-frequency hyperentangled photon pairs via spontaneous parametric down-conversion(SPDC)processes,where six different paths and two different frequencies are covered.A two-dimensional periodicalχ^((2))nonlinear photonic crystal(NPC)is designed to satisfy type-Ⅰquasi-phase-matching conditions in the plane perpendicular to the incident pump beam,and a perfect phase match is achieved along the pump beam's direction to ensure high conversion efficiency,with theoretically estimated photon flux up to 2.068×10^(5) pairs·s^(-1)·mm^(-2).We theoretically calculate the joint-spectral amplitude(JSA)of the generated photon pair and perform Schmidt decomposition on it,where the resulting entropy S of entanglement and effective Schmidt rank K reach 3.2789 and 6.4675,respectively.Our hyperentangled photon source scheme could provide new avenues for high-dimensional quantum communication and high-speed quantum information processing.

Total ionizing dose and synergistic effects of magnetoresistive random-access memory

A magnetoresistive random-access memory(MRAM) device was irradiated by ^(60) Co c-rays and an electron beam.The synergistic effect of this on the MRAM was tested with an additional magnetic field during irradiation,from which the total ionizing dose(TID) and the synergistic damage mechanism of MRAM were analyzed.In addition,DC,AC,and functional parameters of the memory were tested under irradiation and annealing via a very large-scale integrated circuit test system.The radiation-sensitive parameters were obtained through analyzing the data.Because of the magnetic field applied on the MRAM while testing the synergistic effects,shallow trench isolation leakage and Frenkel–Poole emission due to synergistic effects were smaller than that of TID,and hence radiation damage of the synergistic effects was also lower.

Total ionizing dose effects in pinned photodiode complementary metal-oxide-semiconductor transistor active pixel sensor

A pinned photodiode complementary metal–oxide–semiconductor transistor（CMOS） active pixel sensor is exposed to ^60Co to evaluate the performance for space applications. The sample is irradiated with a dose rate of 50 rad（SiO2）/s and a total dose of 100 krad（SiO2）, and the photodiode is kept unbiased. The degradation of dark current, full well capacity,and quantum efficiency induced by the total ionizing dose damage effect are investigated. It is found that the dark current increases mainly from the shallow trench isolation（STI） surrounding the pinned photodiode. Further results suggests that the decreasing of full well capacity due to the increase in the density, is induced by the total ionizing dose（TID） effect, of the trap interface, which also leads to the degradation of quantum efficiency at shorter wavelengths.

X-ray irradiation-induced degradation in Hf_(0.5)Zr_(0.5)O_(2) fully depleted silicon-on-insulator n-type metal oxide semiconductor field-effect transistors

The n-type ultrathin fully depleted silicon-on-insulator(FDSOI) metal-oxide-semiconductor field-effect transistors(MOSFETs),with a Hf_(0.5)Zr_(0.5)O_(2) high dielectric permittivity(high-k) dielectric as gate insulator,were fabricated.The total ionizing dose effects were investigated,and an X-ray radiation dose up to 1500 krad(Si) was applied for both long-and short-channel devices.The short-channel devices(0.025-0.100 μm) exhibited less irradiation sensitivity compared with the long-channel devices(0.35-16 μm),leading to a 71% reduction in the irradiation-induced drain current growth and a 26% decrease in the shift of the threshold voltage.It was experimentally demonstrated that the OFF mode is the worst case among the three working conditions(OFF,ON and A110) for short-channel devices.Also,the determined effective electron mobility was enhanced by 38% after X-ray irradiation,attributed to the different compensations for charges triggered by radiation between the highk dielectric and buried oxide.By extracting the carrier mobility,gate length modulation,and source/drain(S/D)parasitic resistance,the degradation mechanism on X-ray irradiation was revealed.Finally,the split capacitance-voltage measurements were used to validate the analysis.

Effect of Tetrabutylammonium Bromide on Enzymatic Polymerization of Phenol Catalyzed by Horseradish Peroxidase

In this article tetrabutylammonium bromide （TBAB） was first added in buffer to compose a convenient and environmentally friendly system, and enzymatic polymerization of phenol catalyzed by horseradish peroxidase （HRP） could proceed efficiently in this system. When TBAB was added, the most conversion of phenol could reach 99.1%. The phenol polymer was considered to consist of a mixture of phenylene （Ph） and oxyphenylene （Ox） units by IR analysis, and the ratio of phenylene to oxyphenylene units （Ph/Ox） was measured by titration. Moreover, the effects of the dosage of horseradish peroxidase （HRP） and pH value on the conversion of phenol were investigated. The reaction performed very effectively in this novel system when the addition of HRP was only 0.2 mg. In all cases, the weight-average molecular weight calculated by GPC-SLS was in a range from 12000 Da to 30000 Da. The phenol polymer prepared in the present research possessed good thermal stability shown by TG analysis.

Iridium-catalyzed direct ortho-C–H amidation of benzoic acids with sulfonylazides

A mild and efficient iridium-catalyzed ortho-C-H amidation with sulfonyl azides by weakly coordinating carboxylic acid was demonstrated, which provided a novel approach to anthranilic acid derivatives.